Amid its strategic pivot toward the Asia-Pacific, America’s long-standing alliance with South Korea is expected to deepen to better deal with an increasingly bellicose North Korea and a rising China.

Forged during the 1950-53 Korean War, the alliance, which had focused on deterring the North, has evolved into a more multi-faceted, value-based partnership. It now goes beyond the bilateral level to jointly tackle regional and global challenges such as non-proliferation and anti-terrorism.

“The two countries (Korea and the US) are taking joint action to respond to global issues such as proliferation of weapons of mass destruction, climate change, energy and food crisis, poverty, etc.,” Foreign Minister Kim Sung-hwan said during a speech at the World Affairs Council in Los Angeles last month.

“Korea and the US are sharing not only the interests, but also values.”

In support of America’s global initiatives to tackle threats from terrorism and proliferation of WMDs, South Korea sent its troops to Iraq in 2004 and Afghanistan in 2010.

In March, Seoul also hosted the second Nuclear Security Summit, a premier forum US President Barack Obama has pushed to realise his vision of a “nuclear-free” world. It has joined the US-led anti-Iran sanctions at the expense of its economic ties with the Islamic republic.

The Seoul government is also taking steps to deploy troops to help stabilise South Sudan where another Sino-US competition is emerging over the resource-rich, conflict-laden African state.

Some dismiss Korea’s diplomatic and military moves in sync with America’s global strategy as the “trap” of the alliance. Others, however, say a reliance on the US is inevitable to deal with a growing security uncertainty in the region.

The alliance’s efforts to grow out of the Cold-War era frame have been overshadowed by North Korea’s relentless saber-rattling and China’s growing assertiveness in Asia.

After a series of North Korean provocations in recent years including the sinking in 2010 of the corvette Cheonan, the allies refocused on reinforcing joint deterrence against the belligerent state.

As China did not take any action to discourage Pyongyang’s provocative behaviour when its impoverished ally shelled the border island of Yeonpyeong in 2010, Seoul and Washington reinforced their security ties.

“The deepening of the alliance between South Korea and China serves the strategic interests for both countries,” said Kwon Tae-young, advisor to the non-profit Korea Research Institute for Strategy.

“For the South, a stronger alliance could serve to better deter North Korea while the US could think of the alliance from a broader strategic perspective to help keep China in check.”

Enhancing deterrence against NK

A flurry of recent reports suggested that the US is considering turning the 2nd Infantry Division into a combined unit of the allies and maintaining the 210th Fires Brigade of the division north of Seoul rather than relocating it down to Pyeongteak as planned.

The envisioned unit appears to be similar to America’s 1st Corps that temporarily led a combined force to defend the western frontline after the end of the Korean War in 1953. The allies’ corps led the US 2nd and 7th Infantry Divisions and Korea’s 1st, 5th and 6th Corpses.

US Forces Korean Commander Gen. James D. Thurman also reportedly floated the idea of maintaining the allies’ Combined Forces Command, which is to be dissolved after Seoul retakes wartime operational control in December 2015.

The US has been working to relocate its troops in Seoul and north of the capital down to Pyeongtaek as part of its global troop realignment scheme designed for “strategic mobility”.

The moves appear aimed at enhancing deterrence against North Korea, while some experts argue that they are also part of a broader US strategy to capitalise on the alliance to keep China in check.

“In the wake of North Korea’s two lethal uses of force in 2010, combined with recent threats and a tenuous political transition, it is essential to reestablish deterrence,” said Patrick M. Cronin, senior director of the Asia Programme at the Centre for a New American Security.

“Bringing US forces up to full strength, enhancing alliance interoperability, and exercising in the Yellow Sea are all ways to accomplish that vital objective.”

Rather than retreating to the non-frontline areas, stationing the combat unit near the heavily-fortified border is apparently a potent show of America’s commitment to the defense of the South.

But from America’s broader strategic perspective, its stronger readiness south of the border could help deter the increasingly assertive Asian power.

“Given its proximity to China, the US could use the land-based unit in South Korea as its outpost to deal with the Asian power,” said a security expert, who declined to be identified.

“The US needs to establish ground bases capable of neutralising China’s missiles that form the centerpiece of China’s anti-access/ area-denial capabilities, which obviously pose a grave threat to America’s once formidable aircraft carriers.”

Dilemma for S. Korean military

The South Korean military faces a dilemma in its balancing of resources among the three armed services. To deal with threats from North Korea and neighboring states challenging its maritime sovereignty, it needs to bolster both ground and naval power.

As the US seeks to reduce its military footprint while focusing on its naval and air forces, and intelligence, surveillance and reconnaissance capabilities, concerns have arisen over the possibility of a diminished American ground support in the event of another armed conflict on the Korean Peninsula.

The US now plans to reduce its Army troop level to 490,000 from the current 570,000 and the number of marines to 180,000 from the current 200,000 over the next decade.

On top of that, Seoul is to retake wartime operational control from Washington in December 2015, meaning that it will lead both wartime and peacetime operations with the US playing a supporting role.

Given this, experts say that the South Korea-US Operation Plan 5027 centering on an all-our war with the North will no longer be realistic. Under the joint war plan, the US is to dispatch its 690,000 troops to the peninsula and mobilise some 160 military vessels and 2,500 aircraft within 90 days of the outbreak of a war.

“During a decade of costly warfare in Afghanistan and Iraq, America’s economy deteriorated while China has risen. As they were mired in quagmires during this war, they now try not to deploy their ground troops for a long period,” said Kwon Tae-young of the Korea Research Institute for Strategy.

“Thus, we can say that America’s willingness to offer ground support has declined.”

The need to strengthen ground troops also comes from the yawning gap between its ground troop number and that of North Korea’s.

Seoul seeks to reduce its ground troop number to 418,000 by 2020 and to 387,000 by 2030 from the current 520,000. Pyongyang now has around 1.02 million ground troops whose basic service period is known to be more than six years, more than three times longer than that of South Korean troops.

In case of North Korea’s collapse, South Korea also needs a massive ground force to conduct stabilisation operations, experts noted.

But South Korea cannot ignore the importance of its naval force to secure its maritime interests. Japan continues to claim sovereignty to its easternmost islets of Dokdo and China makes a jurisdictional claim to Ieodo, a submerged rock in the overlapping exclusive economic zones of the two nations.

“In this century, crucial interests lie in sea areas, meaning naval power is of great importance. Given that Korea’s economy relies heavily on overseas trade, we also think about securing our shipping routes,” said Kwon.

Some experts also point out that given growing uncertainties in the regional security conditions in the future, Korea should reduce its reliance on America’s air and naval power and bolster its own self-defense capabilities.

“Now we share the security interests in this region with the US. But we never know how the situation will change a decade or two decades later,” said a security expert, declining to be named.

Calls for increasing burden-sharing cost

As the US seeks to cut defense spending, its demand for increasing Korea’s share of the cost for maintaining some 28,500 US troops on the Korean Peninsula is expected to increase.

Korea’s share stands at about 42 per cent of the cost for US troop sustainability here. Washington has long demanded that the share be raised to 50 per cent.

Since 1991, the two sides have had eight rounds of negotiations over the rate of Seoul’s contribution to the Special Measurement Agreement fund.

The issue of the so-called burden-sharing cost has been a source of friction as the allies have been at odds over Korea’s share and its contribution methods ― whether to provide cash or goods.

As civic groups, whose status has been elevated through the country’s industrialisation and democratisation, have raised their voice against the increase of Korea’s share, the issue has gotten more sensitive.

The decision in the latest round of negotiations over the SMA fund is to remain effective until 2013. For the burden-sharing for 2014, the ninth round of talks should resume.

“Using its superior position in the negotiations over the SMA fund, the US unfairly demanded that Seoul shoulder the financial burden for what they are supposed to shell out,” said Cho Young-sun, a member of the civic group Lawyers for a Democratic Society.

But some experts argue that South Korea needs to increase its share of the payment considering that the bilateral alliance with the U.S. continues to take on a great importance in the face of North Korea developing missiles and nuclear weapons.

Source of cracks in alliance

The alliance between Korea and US has had its own share of ups and downs since it was forged six decades ago.

One of the obstacles to the ties was anti-American sentiment fanned by misunderstandings, inordinately emotional responses to US military issues and elevated civil society demanding an equal relationship with America.

Anti-American sentiment among progressive political circles originated from the 1980s when pro-democracy movements were brutally quashed by Chun Doo-hwan, a general-turned-president.

They claimed that the US backed Chun as he carried out a bloody military operation given that the US held command authority over all Korean troops. Korea’s first President Syngman Rhee handed over the authority to the US some 20 days after the Korean War broke out on June 25, 1950.

This sentiment against the US peaked in 2002 after two middle-school girls were killed after a US military vehicle accidentally ran over them. The accident sparked nationwide candle-lit vigils and led to the election of Roh Moo-hyun who sought to balance the alliance.

Continuing crime involving American troops here have also added to anti-US feelings.

“There are some who show an ‘allergic’ response to issues involving the US In particular, progressive pro-North Korea people here make such emotional responses out of the nationalistic mentality,” said Yoon Pyung-joong, a professor of political science at Hanshin University.

“Whether it is about trade or military, I hope we remain cool, reserved, less emotional and confident in the relationship with the US.”

Differing views over whether to engage Pyongyang or not have also been a sensitive topic between the allies.

Liberal former President Roh Moo-hyun sought to embrace the impoverished neighbor as his predecessor Kim Dae-jung did. This was at odds with the policy of the George W. Bush administration that branded North Korea as part of the axis of evil along with Iran and Iraq in 2002.

Conflicting interests have been a hindrance to the alliance as well. In the latest case, Korea joined the US-led anti-Iran sanctions despite its possible negative impact on trade and oil supply.

Importance of trust between Korea, US

In the event of a sudden collapse in North Korea, close cooperation between South Korea and the US will be crucial as they could move into the country to stabilise it under the UN banner.

In that case, the possibility of peninsular reunification emerges, although China could step in to play its own role. Experts said under this situation, trust between the two allies will be crucial as it could affect how far the US will help South Korea stabilise and unify the peninsula.

“After the stabilisation work, the question is how much the US is willing to help South Korea which aims for national reunification,” said Chung Sung-yoon, research professor at the Ilmin International Relations Institute of Korea University.

“Due to partisan politics in Korea, the alliance could be affected either negatively or positively after a change of government. We need to sufficiently prepare for possible instability in the communist state, capitalising on the alliance.”